Wrapping

Is this an issue? (Quest Air, Groveland, Florida, USA)

http://ozreport.com/9.188#1

I once had a pro-tow Spectra bridle snag or wrap around the end of the tow rope when there was no ring or carabineer at the end of the tow rope, just a loop.  I had two barrel releases and I just released the other barrel and let my bridle go by-bye.

So the loop at the end of the tow rope was the real problem.  With metal rings, links, carabineers, there doesn't seem to be quite that problem.  But it is more interesting than that.  I also wrote in this article a statement that Tracy Tillman from Cloud 9 made:

He told me that he saw Jim Prahl at Quest Air, a few years ago, wrap the upper portion of his Spectra V-bridle around the ring at the end of the tow rope and have the tug almost tuck his glider.  He also told me that he had heard that this had been an ongoing problem, that every once in a while Spectra V-bridles wrapped around rings.

Well Jim Prahl is here at the Santa Cruz Flats Race so on the practice day I had an extensive discussion with him about this incident and about carabineers in general.

First, as to the incident, this was actually a test and in the test Jim Prahl actually tied a rag to one end of the spectra rope on his shoulders so that it would be sure to catch and hold as the rope slid through the loop at the end of the V-bridle coming from the keel.  He was trying to test to see if the weaklink at the keel end of the V-bridle line would break when the rag stuck.  Well it didn't.

What happened when Jim released the barrel on his shoulder and the rag and bridle stuck in the line of the V-bridle, was that the nose of the Wills Wing Falcon pitched straight down instantly.  Jim was left towing from the keel only at about a foot in front of the carabineer/hang loop.

Now Jim was not so dumb as to do this test without a backup plan (although he didn't expect the glider to pitch down so rapidly).  He had the weaklink from the V-bridle line attached to a spinnaker shackle that was connected to a brake type release.  He had his hand on the brake lever.  When he released the barrel release, and the rag snagged the line, he didn't have time to hit the brake lever before the nose went over (and the weaklink didn't break).  He then hit the brake lever and fortunately the glider recovered (it was a Falcon after all).

The point of this experiment was to see if it was okay to just release from the barrel release and do away with the expensive brake lever, cable assembly, and spinnaker release.  Just connect the V-bridle line to the keel with a weaklink that would supposedly break if the shoulder line snagged in the loop (which I proved was possible).  Jim proved that this was perhaps not a good idea.

A lot more on carabineers, rings and snap links in the next article.

Again, I have a direct personal and minor financial interest in the issues raised by this discussion.

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